


Off the Spiral: Glowstick

by GreyInnocence



Category: Prince of Tennis
Genre: Humor, M/M, Romance
Language: English
Status: Completed
Published: 2010-09-13
Updated: 2010-09-13
Packaged: 2017-10-11 19:22:53
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,483
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/116040
Author URL: https://archiveofourown.org/users/GreyInnocence/pseuds/GreyInnocence
Summary: <blockquote class="userstuff">
              <p>Inui's new juice has a surprising effect on Kaidoh.</p>
            </blockquote>





	Off the Spiral: Glowstick

A/N: Remember the last time we posted something (besides our weekly things)? We don't either.

So, this Off the Spiral is based on the scene in The Notebook during which Inui and Kaidoh are given a truth during Truth or Dare about the weirdest effect Inui's juices have ever had on Kaidoh.

Disclaimer: It's all Konomi-sensei's. Trust us, we wish we could own it.

Warnings: Lemony goodness.

—

Off the Spiral: Glowstick

"It won't do anything weird, right?"

"Of course not." Inui smiled. It wasn't very reassuring.

Kaidoh hesitantly took the glass and quickly downed the contents.

When he didn't immediately feel the need to vomit, he stared worrying. "Are you sure?"

"Yes." Inui jotted something down in his notebook. "Why?"

"I don't feel sick." Last time he hadn't felt sick, everything had smelled like Echizen's tennis socks for a week.

"You don't look sick either."

"Exactly. I should be puking all over the room. Since I'm not, I have to assume that your juice is slowly eroding my internal organs."

"Don't exaggerate, Kaoru." Inui looked at him for a moment. "If you're that concerned, however, perhaps you should take your clothes off so I can give you a more thorough examination."

Kaidoh didn't feel in the mood at all at the moment, but thankfully Inui seemed legitimately interested in laying his fears for his health to rest, so he stripped his tank top over his head and then pushed his shorts down his legs.

"Boxers too, Kaoru."

Kaidoh's hands paused over his boxers. "You're not going to try anything, are you?"

"Not unless it proves necessary."

Apparently it was necessary, as he was sprawled across Inui's chest half an hour later, naked and sticky with sweat and semen.

"There isn't anything wrong with you, Kaoru. Maybe you've become immune to them..."

Kaidoh shrugged. It didn't matter right now anyways.

—

The next day Inui cornered him in the club house after morning practice. "Are you still feeling okay?" Inui asked, pinning his kohai between the lockers and his body.

"I'm fine, Inui-sempai." Kaidoh ducked out under one of Inui's arms.

"You're still coming over after practice this evening, right?"

Kaidoh's cheeks pinked. "Yes..." Inui's parents were gone for the weekend, and Kaidoh was supposed to stay over. Regardless of having been with Inui for three years now, he was still rather shy about staying the night.

Eiji and Oishi came in then, having won their practice match with a third year doubles team.

"I'll see you this afternoon, then." Inui kissed Kaidoh's forehead, making the younger boy blush. "Don't be late to class."

—

When after-school practice had ended that afternoon, Inui and Kaidoh left the school together amidst catcalls from Momo and Eiji. "I just need to go home to get my things," he murmured, looking at his feet in embarrassment. People knowing about his sex life—even the fact that he had one—was another thing he wasn't yet comfortable with.

"Of course," Inui replied.

There was an awkward pause before Momo rode past on his bike, wolf-whistling loudly as he pedaled off towards the middle school.

"Bastard!" Kaidoh called after him.

They really didn't fight because they hated each other so much anymore; Tezuka appointing them captain and vice captain had seen to them at least being able to work together, though they still bickered incessantly because they could. Inui figured they'd be back to their old ways soon enough simply because they didn't need to work together anymore.

Inui put a hand on Kaidoh's shoulder, making him tense. "He's just jealous that Echizen won't have intercourse with him."

Kaidoh blushed. "Fushuu, Sempai shouldn't know those things about Echizen and the monkey."

"Well, there's only a two percent chance Echizen will have sex with Momoshiro before the end of his third year of junior high, and that is in the case that he is inebriated..."

Kaidoh tuned out Inui's data on Momo and Echizen's sex life as he felt himself pale.

"Their relationship alone defies data, really—Kaoru, we have reached your house."

Kaidoh paused and looked up. He'd been about to walk right past. "Oh." He flushed. "Sorry."

"You seemed to be lost in thought. Is something troubling you?"

"No, Sempai." _Just your disturbingly extensive data on the rest of the team's sex lives._

Kaidoh opened the door, calling out that he was home.

"Kaoru, is Inui-kun with you? Invite him in! Your grandmother is here!" his mother called from the kitchen.

Kaidoh looked over his shoulder at Inui, who was taking off his shoes. "Um, Inui-sempai, my grandmother is..." He wasn't sure how to finish the warning.

"I'll behave." Inui put an assuring hand on his shoulder.

Kaidoh nodded and led Inui to the kitchen, when his mother and grandmother sat at the table with tea and a tray of cookies.

"Hello, Kaoru. It's be a while since I last saw you." The old woman took a drink of her tea.

"Hello, Grandmother." Kaidoh bowed stiffly.

"Introduce your friend," she ordered politely.

"R-right." Kaidoh flushed. "Grandmother, this is Inui Sadaharu. Inui-sempai, this is my Grandmother."

Inui, who had been mostly raised by his own grandma, liked to think old people liked him. He stepped forward, taking her hand in his and falling into a low bow. "Kaidoh-sama, I am pleased to make your acquaintance. Kaidoh has told me many wonderful things about you."

Kaidoh's mother pressed a hand to her mouth, smothering the giggles that threatened to escape her throat. She looked at her son, who looked utterly confused.

"Oh, you're absolutely charming," Kaidoh's grandmother fawned. "Kaoru, why haven't I met this nice boy before?"

"Er—well—"

"Kaoru spends a lot of time at Inui-kun's house, Mother," Kaidoh's mother told her. "Doing homework, of course." She winked at Kaidoh, who blushed furiously and looked away. "Kaoru's math and science grades have risen dramatically since he's been friends with Inui-kun."

"As a matter of fact, Kaidoh and I were just going to my apartment so he can help me with some experiments," Inui said. "I hope you're not disappointed I'm taking your grandson away from you, Kaidoh-sama."

"Don't be silly, dear," she replied, patting his hand. "You're obviously a very good influence on Kaoru, I'm sure he's in good hands."

Kaidoh held back a snort. Anyone who knew Inui well wouldn't put his name and "good influence" in the same sentence.

"Kaoru," his mother started, "your things?"

Kaidoh was brought out of his mental scoffing. "Oh, right. I'll be right back, Inui-sempai."

"Take your time." Inui grinned over his shoulder at the younger boy.

Kadoh left the room, hearing his grandmother comment about how forgetful her grandson was, and wouldn't Inui sit down, and get the boy some tea, dear! That was okay. He didn't like the grouchy old woman very much either.

Kaidoh stuffed his things into a bag, along with a few things he needed to do for homework in the event they had downtime. He went back downstairs, immediately colliding with Hazue, who had just gotten back from school.

"Watch where you're going!" Hazue shouted.

"Sorry," Kaidoh muttered as he gathered a few things that had fallen out of his bag.

"And he's clumsy too!" His grandmother remarked from the kitchen.

Inui chuckled. "Only when he's nervous. It's rather endearing though. I think."

Kaidoh flushed and scowled. "Inui-sempai, I'm ready," he called into the living room, preferring to stay in the foyer.

"Coming, Kaidoh!" Inui answered cheerfully. "Kaidoh-sama, it was such a pleasure meeting you, I hope I'll see you again soon."

"I feel the same way, my dear. Take good care of my grandson, he can be quite absent-minded sometimes..."

"Oh, I don't think that's true, Kaidoh-sama. Kaoru is very focused and attentive in the be—ah—tennis court."

 _Oh God. Inui-sempai, I'm going to kill you._

He put on his shoes and waited for Inui to put on his before they started toward Inui's house.

"Did you really have to say that to my grandmother?" Kaidoh grumbled as soon as they came to a stretch of sidewalk void of people. "You may as well have told her about us."

"But Kaoru, I don't care if she knows about us."

"I do! She'll probably throw a fit about how I'm an abomination and whatnot—and I don't care what she says about me, but if she says anything bad about you I'll probably go off on her, and I know that's disrespectful, but—" Kaidoh faltered. "But you're more important than that, I guess."

Inui smiled and pulled Kaidoh against his chest. "Thank you, Kaoru, but if that is your grandmother's opinion of our relationship, then I don't care what she says about either of us; she doesn't deserve to be heard." He kissed Kaidoh softly on the lips. "And I don't ever want to hide our relationship, especially from family."

Kaidoh nodded. "Okay..."

"Come on." Inui urged him towards a bus stop that would get them closer to his apartment faster than walking would.

"We never take the bus, though..." Kaidoh frowned.

"You're not looking so well. If I had to guess there's between a seventy and eighty percent chance that you got an adrenaline spike when you realized your grandmother was at your house and are going to crash soon..."

Kaidoh's blush told Inui that he was right. He thought of taking Kaidoh's bag from him as they stood but figured Kaidoh would become irritated. He settled for putting a hand on his lower back and letting Kaidoh rest against his shoulder once they were on the bus.

Inui woke him up at the stop before theirs. He had draped his regulars jacket over Kaidoh after he'd fallen asleep and now put it back on as he pulled the rope to let the driver know they needed off.

"Thank you!" they chorused as they stepped off the bus.

Kaidoh rubbed his eyes sleepily. "I'm sorry I feel asleep, Inui-sempai."

"It's quite all right, Kaoru. You'll be refreshed now for this evening's activities."

Kaidoh flushed. "Such as...?"

"Well," Inui said with a grin, his glasses glinting, "I need to examine you again to ensure that the juice you drank yesterday didn't take time to take effect. Don't worry," he added, "I'm sure there weren't any adverse effects. You seem perfectly well."

Kaidoh made an affirmative noise end allowed Inui to guide him through the apartment complex.

"We're home," Inui called into the apartment, even though he knew no one else was.

The boys kicked off their shoes and went to Inui's bedroom.

"Sit." Inui motioned to his bed as he picked up a notebook labeled "Kaidoh" from his desk, then pulled a stethoscope and a mini flashlight from the drawer. "You're sure you feel perfectly fine?" Inui asked, shining the flashlight in Kaidoh's eyes. "You haven't felt queasy or dizzy?"

"No. I've felt fine."

"Say 'ah'."

Kaidoh opened his mouth wide, and Inui shined the flashlight down his throat.

"Your tonsils aren't enlarged," Inui said, scribbling in his notebook. "Take your shirt off, please." Kaidoh obliged, and Inui pressed the stethoscope against his chest. "Breathe."

"Inui-sempai, I feel like this is a doctor's appointment."

"Good. I _am_ giving you a standard checkup."

Well, there was nothing "standard" about what Inui's so-called checkups usually led to, but Kaidoh didn't say so, just let Inui continue his work.

After a thorough check up, Inui set down the notebook, stethoscope, and flashlight. Kaidoh had pulled his legs into the bed and was rubbing at a smudge of dirt on his ankle that he'd missed when he'd showered after practice.

"Would you like to take a quick shower?" Inui suggested.

Kaidoh shrugged. If he did shower, it wouldn't be quick. Inui would follow him in and it would really just be counter-productive.

Inui slipped behind Kaidoh on the bed, pulling the smaller form back against his chest.

"You're tense." Inui kissed the back of his neck. "Did your grandmother really bother you that much? There is also a fourty-three percent chance it is nervousness about your stay here and a twenty-two percent probability it has to do with the possibly unknown effects of my juice... "

Kaidoh tilted his head to give Inui more access. "Fushuu..."

"It's also quite possible that it's a combination of all three. I must say, Kaoru, I don't understand why you feel so nervous about staying with me. Your parents have expressed that they are perfectly comfortable with our relationship—though they remain unaware of its sexual nature—"

"They're not stupid, Inui-sempai, just because we haven't told them doesn't mean they don't know, or at least suspect."

"Ah, so that's it. You don't want your parents to know you're having sex."

"I don't particularly want anyone to know. I'm not embarrassed by it, before you ask, I just... think it's private."

Inui shrugged. "It's not like everyone doesn't eventually."

"Yeah, but... Inui-sempai, it's not the... that." Kaidoh paused, his face flushing brilliantly. "It's just different, when we're together all weekend."

"I suppose it does seem more intimate." Inui pushed up his glasses.

Kaidoh nodded once, resting against Inui. "Not that I don't like spending the night here. It's nice to be able to take things slow... and not have to worry about getting caught..."

Inui 'hmm'ed in agreement, kissing down Kaidoh's neck and sneaking a hand under his tank top. "Arms up, Kaoru."

Kaidoh raised his arms so Inui could slip the tank top off him and toss it across the room, then scooted around in front of Kaidoh so he could access Kaidoh's chest.

"Hips."

Kaidoh laid back and lifted his hips so Inui could tug off his shorts. Inui nipped at his kouhai's collar bone.

Kadioh ran his hands around the back of Inui's neck and carded his fingers into the spikey black hair.

"Kaoru..." Inui pulled back to look at Kaidoh.

"Hmm?" Kaidoh was still thinking.

Inui made a small chuckling noise and removed his glasses. Kaidoh's attention was suddenly focused entirely on him, and Inui grinned when his kohai knocked him back onto the bed and straddled him.

"There was a one hundred percent chance that would happen," Inui informed him.

"Shut up, Sempai."

Inui pushed Kaidoh off of him and stood up to disrobe. Kaidoh flushed and turned away.

"Sempai?"

"Yes, Kaoru?" Inui ran a hand though his hair, enjoying the kohai's embarrassment.

"Lights?"

"Of course." Inui jotted down a number in his notebook and stepped towards the door to flick off the lights.

Kaidoh let Inui pull him against his chest when he slid back onto the bed.

Inui sealed his lips with Kaidoh's. He didn't need the light or his glasses to see Kaidoh or know where he was or what his flailing limbs were doing. The analyst's hands skimmed down Kaidoh's sides. Kaidoh arched away from the hands.

"Inui-sempai, that tickles."

Inui hummed a laugh. "Sorry."

Kaidoh grunted. Inui's lips had attached themselves to the side of Kaidoh's neck beneath his ear.

"That's gross." Kaidoh pushed Inui back after he laved his tongue across the younger boy's throat.

Inui smirked. "I like the way you taste."

Kaidoh could feel his face flush.

"Don't you like the way I taste, Kaoru?"

"I don't know, Sempai," Kaidoh mumbled. "You just taste like... skin."

Inui 'hm'd.

"But—well, I mean, Inui-sempai, I don't _dislike_ it." Kaidoh mentally fretted for a moment before deciding that the best course of action was probably to make Inui forget about this conversation. Momentarily. Inui would no doubt keep it in the back of his mind and bug him about it later.

Kaidoh pulled Inui forward for a kiss, moaning into Inui's mouth as the older boy's hand found his cock. "Besides," Kaidoh murmured, flushing, "I could talk for hours about all the things I like about you."

"Oh?" Inui said curiously. "Go on, then."

"Inui-sempai," Kaidoh groaned. "I can't think properly with you doing that, and if you stop I can't be held responsible for my actions."

"Very well, Kaoru, we will talk about this later."

Kaidoh bit Inui's shoulder when the older boy tightened his grip on Kaidoh's erection.

"I thought you didn't like how I tasted..." Inui laughed.

Kaidoh's eyes closed and he tried to thrust into Inui's hand. "Sempai!"

Inui pressed a kiss to his temple. "Be patient, Kaoru."

He reached under his pillow, procuring a small bottle of lube. He coated his fingers generously and teased Kaidoh's entrance. Kaidoh squirmed on the mattress below Inui, trying to keep his legs parted and his hands off of his spectacle-less sempai.

"Inui-sempai," Kaidoh groaned, fisting the sheets. "Please..."

"'Please' what?"

"Don't tease me." Kaidoh glared up at Inui, though he knew Inui couldn't see his expression in the dark and without his glasses. Inui probably knew anyway.

Inui complied with this request, slipping his middle finger inside Kaidoh halfway. "I wouldn't tease you if you weren't so fun to tease."

"Jerk."

The data player wrapped his fingers around Kaidoh's erection, rubbing the tip with his thumb, making Kaidoh's hips jerk up. "I can't help enjoying it. You respond so animatedly, it's very sexy."

"You are the most blunt person in the universe."

"It's part of my charm, wouldn't you say?"

Kaidoh answered with a gasp as Inui's finger twisted inside him.

A chuckle came from his throat while he made quick work of adding a second finger. He couldn't help smirking.

"Don't be so smug."

"I think I have every right to be smug, based on your ragged breathing and the fact that your heart rate has increased by twenty-five percent."

"Ngh!" Kaidoh closed his eyes tightly as Inui leaned down to flick his tongue over the tip of the first year's erection.

Inui scissored his fingers to add a third without much trouble and let his fingertips come dangerously close to prodding Kaidoh's prostate, smirk growing when Kaidoh growled in frustration.

"Ready?" The hand on Kaidoh's shaft was removed to pluck the lube from a fold in the sheets. His hips pressed back to Inui's hand in answer.

Inui squeezed a dollop of the viscous fluid onto his palm and covered his cock with it, then crawled between Kaidoh's legs, his arms supporting him on either side of the younger boy. Bringing one hand down to take hold of his erection, he pushed slowly inside.

Kaidoh grasped Inui's arms, his nails digging into his boyfriend's skin. Inui didn't complain—never did; he was used to Kaidoh's scratching habit—just pushed his hips forward a bit further, smirking at Kaidoh's whimper when he paused again.

"Inui-sempai," Kaidoh groaned impatiently. "I can take it, you don't have to go so slow."

"Didn't I just tell you how much I enjoy teasing you?"

Kaidoh made a breathy disappointed sound, loosening his grip on Inui's arms.

Inui snorted. That reverse psychology wasn't going to work on him. Instead he let his hand wander to were they were connected and trace around Kaidoh's stretched entrance. Kaidoh gasped and his passage tightened around Inui's cock, the sensation making him buck forward and seat himself within his kouhai.

Kaidoh took a deep, shaky breath before he tangled his hands in the hair at the nape of Inui's neck and pulled his sempai down for a kiss. "Please," he mewled into Inui's neck as they parted.

Inui tipped Kaidoh's chin up, kissed his forehead, and smoothed his bangs back. Then he settled back and pulled himself out of his boyfriend the tiniest bit, letting his thrusts build up from the slow shallow pace to a faster deeper one that had Kaidoh groaning with each thrust.

It wasn't long before Inui felt his orgasm nearing, and Kaidoh was showing tell-tale signs as well: his moans grew more wanton, his hips rocked more erratically, he tightened around Inui's cock. "A bit more, Kaoru?" he asked in a strangled voice.

Kaidoh managed a noise that sounded consenting, and Inui grasped his erection, stroking jerkily until they both came almost in unison. Inui pulled out and laid his arm across Kaidoh's chest, nuzzling Kaidoh's shoulder.

"Inui-sempai."

"Hm?"

"What. The _hell_. Have you done to me."

Inui blinked and sat up. "What are you talking about, Kaoru?"

Kaidoh shoved Inui's glasses into his hand. When Inui had put them on, Kaidoh pointed to his stomach.

It was... glowing. Or, rather, parts were. Lines. Lines reminiscent of—

"My SEMEN is GLOWING in the DARK."

Inui didn't know what to say.

"I told you that rancid juice of yours was probably eroding my internal organs! This must be a side-effect of my _imminent death_ —"

Inui blinked and watched Kaidoh flail with his inability to form coherent words. Then he took off his glasses, setting them on the nightstand, wrapped his arm around Kaidoh, pinning the thrashing arms to the younger boy's sides, and pulled him back into the blankets.

"You are not dying. Go to sleep, Kaoru."


End file.
